地铁曲线段Vanguard扣件减振效果分析

为研究Vanguard扣件在地铁曲线段的减振效果,以北京地铁5号线某曲线段为例,分别对DTVI_2扣件和Vanguard扣件下列车运行引起的地表振动响应进行现场测试.并通过建立相应的三维动力学数值模型对比分析了两种扣件在直线段和曲线段的地表动力响应特性和衰减规律.通过分析振动响应峰值、最大垂向计权Z振级及插入损失,研究了Vanguard扣件的减振效果.根据现场实测以及数值分析结果可知:列车运行引起的地铁曲线段地表动力响应高于直线段,圆曲线和缓和曲线的动力响应特性类似且量值接近;列车运行引起的地表横向及垂向动力响应随距线路中心线横向距离的增加而呈起伏式衰减;列车运行于DTVI_2扣件和Vanguard扣件的轨道上时引起的地表垂向振动响应显著的频段分别位于60Hz和30Hz附近;Vanguard扣件减振效果显著,对曲线段水平向振动响应的减振性能良好.

Analysis of vibration damping effect of Vanguard fastener in curved segment of subway line

In order to study the vibration reduction effect of the Vanguard fastener in curved segment of subway line 5 in Beijing,field tests are conducted to measure the ground surface vibration response when the train moving on track with DTVI2 fasteners and Vanguard fasteners respectively.The three-dimensional dynamic numerical models are established to comparatively analyze the characteristics of dynamic response of straight line and curved segment of subway line and to obtain the attenuation law of dynamic response of the two fasteners.The damping effect of Vanguard fasteners is researched by analyzing the peak value of vibration response,the maximum Z-weighted vibration level and the insertion loss.According to the results of field measurements and numerical analysis,several conclusions are derived as follows.The ground surface dynamic response of the curve section in subway line is higher than the straight one,and the main response of curved section is the lateral vibration.The dynamic response amplitudes of the curved section and the transition curve section are almost the same.The lateral and vertical dynamic response of the ground surface caused by the train operation is fluctuating with the increase of the horizontal distance from the center line of the track.The significant frequency band of ground surface vertical vibration response induced by the train operation with DTVI2 fasteners and Vanguard fasteners are located near 60 Hz and 30 Hz respectively.The vibration reduction effect of Vanguard fastener is remarkable,and it has advantages on the lateral vibration reduction in curve section.